Sencha Touch - How to implement optgroup

Is there a way to split the parameters of the Sencha Touch selection list, similar to using optgroups? I have options that should appear as if they are grouped under several headings. In normal HTML markup, it looks something like this:

<select>
  <optgroup label="First Group">
    <option value="A">OptionA</option>
    <option value="B">OptionA</option>
    <option value="C">OptionA</option>
  </optgroup>
  <optgroup label="Second Group">
    <option value="D">OptionA</option>
    <option value="E">OptionA</option>
    <option value="F">OptionA</option>
  </optgroup>
</select>

Thanks for your time in advance!